panic: vrele: ref cnt (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2a2497efc5fa add aggr(4) to some large ramdisks which I've..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=11134b92580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=49408765328e16b4e501

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ed51a5db7e23/disk-2a2497ef.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/97c3727a45c8/bsd-2a2497ef.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6eceb0c7058f/kernel-2a2497ef.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+494087...@syzkaller.appspotmail.com

panic: vrele: ref cnt
Starting stack trace...
panic(ffffffff83347ced) at panic+0x1ba sys/kern/subr_prf.c:229
vrele(fffffd806cf18ea0) at vrele+0x230 sys/kern/vfs_subr.c:823
fdfree(ffff80002f0fd248) at fdfree+0x286 sys/kern/kern_descrip.c:1215
exit1(ffff80002f0fd248,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215
sys_exit(ffff80002f0fd248,ffff80002a837050,ffff80002a836fa0) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff80002a837050) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a837050) at syscall+0x962 sys/arch/amd64/amd64/trap.c:775
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7e0716ac31f0, count: 250
End of stack trace.


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